Physiological Differences
by CannibaLilly
Summary: A collection of one-shots about the differences in human and Time Lord physiology. Part 1 discusses the superiority, part 2 the inferiority. Both parts are separated into different stories
1. Part 1a

**Part 1.a: Two of everything**

Ever since Donna Noble started travelling with the Doctor she inwardly waited for a prove of his alienness. Of course there was the TARDIS – nothing could be more alien than this ship – but in the end it was just a prove for the old girl's alienness.

Donna kept waiting for such a prove from the Doctor himself, not consciously, but continuously. None appeared and slowly she came to terms with seeing the Doctor as a very smart, very weird human who had somehow grabbed hold of all those alien tools. She wasn't very disappointed about it, maybe she was even relieved. If he had turned out to be the Martian as which she kept addressing him just for the fun of it, it might had crept her out.

And then all that changed. It was a day when they had been running and the Doctor had been talking, a day like every other, that introduced Donna to how alien her Martian really was.

The high-pitched noise of laser guns being fired bounced off the walls around the Doctor and Donna. They were running through the narrow corridors of some kind of mouldy dungeon in a galaxy far away from home.

"Run!" the Doctor shouted unnecessarily over his shoulder. Donna did her best to keep up with him.

"I am!" she replied angrily and completely out of breath and then: "We need a better plan than that."

"Run _faster_!" he proposed. Just when he'd said that he suddenly stopped, his sneakers were sliding over the slick ground and he had some trouble with keeping his balance, but finally he stood completely still and looked to the right side.

Donna reached him seconds later and all but crashed into him. The Doctor caught her and pushed her into a very tiny niche Donna wouldn't have recognized if not for the Doctor. He followed her close behind and pressed Donna against the greasy wall.

She pulled a face, disgusted by the feeling against her clothes and skin.

"Sorry. Shush!" He whispered firmly before the sound of footsteps arose. The Doctor pressed himself even closer against Donna and hence pressed Donna closer against the wall. She twitched her mouth nauseated, but kept quiet.

The group of guards dashed past them and Donna held her breath. Moments later, that felt like ages, the group was gone and the sound of their feet faded away. Their luck that the Doctor had been right. Those aliens had been living in the dungeons for centuries and were all but blind; additionally the smell around here drowned every other hint of their existence.

Donna waited a solid minute after the noises had vanished before she asked: "Are they gone?"

The Doctor waited another second before he replied whispering: "S'pose so, yes."

They exchanged a relieved smile and when the Doctor didn't made any further attempts to move Donna frowned.

"Err, Spaceman..."

"Yeah?"

"Would you shift your arse?" The slick mould felt moist against her skin and she was sure it had started to seep through her top. Donna pressed her hands against the Doctor's chest to make him move and pulled back like she'd burned her hands.

The Doctor awkwardly took a step back before he recognized the shocked expression on his companion's face.

"What's wrong?" he wanted to know.

"Your-" Donna started, not sure how to say it and just pointed at his chest and then looked down at her palms. "_Two_," she managed to say before turned her hands for the Doctor to see.

A frown appeared on his forehead and he looked down at himself.

"What?" he asked, puzzled.

"Two!" Donna repeated, her tone nearly accusing as if he had done this on purpose. "There were two... _things_ beating in your chest!"

"Those two are called hearts, thank you very much," he replied slightly offended.

"Heart**s**," Donna said, emphasizing the 's'. "How come you've got two of them?!"

"I didn't steal one, if that's what you're afraid of," the Doctor mocked. Then he realised that Donna wasn't in the mood for jokes and simply shrugged. "I've been born with two – All Time Lords are," he told her matter-of-factly.

"Why?" Donna asked with a squeaky voice.

"What do you mean 'why'? It's quite useful, so why not?"

Donna didn't say anything to that. She looked at her palms for a moment and then wrapped her arms around herself. The distant sound of more footsteps reminded them of where they were and the Doctor and Donna crept back to the TARDIS without having to hide again.

The blue box was safely trundling through the vortex, far away from any slick dungeons and the Doctor and Donna were sitting in the kitchen over two cups of steaming tea.

"Do you want to talk about the... hearts-thing-y?" the Doctor carefully asked. He hadn't expected that this awareness would startle Donna like that.

Donna shook her head, hesitated and nodded then. Finally she shrugged.

"You could have told me before," she complained.

"Sorry, I'm quite used to them, so I tend to forget arranging caution labels." Gladly the Doctor accepted Donna swatting at his arm, it meant she could deal with his jokes again.

"And you've always had two?" Donna asked.

"Yup," he popped the 'p'.

"Blimey! Doesn't that drive you insane? I mean... are they even beating at the same time?"

The Time Lord chuckled at Donna's newly discovered curiosity for his anatomy. He usually was the explorer more than the explored subject, but this conversation was more enjoyable than he'd expected.

Deciding that learning was still best done by doing, the Doctor stood up and walked around the table, offering Donna his chest to find out herself.

She frowned suspiciously at him at first, but then she really wanted to know and raised her hands to his chest. Carefully she rested her palms against the Doctor's shirt. She felt the soft throbbing against her hands. Not quite at the same time but in an oddly harmonious way, they beat in time.

"Blimey," she repeated and when she recognized she was still touching him, she pulled her hands away.

The Doctor gave her his enthusiastic smile he always wore when he could teach her something new so Donna decided this was the best time to ask.

"What about pulse? Would a doctor - a real doctor, mind you - know you've two hearts when he feels your pulse?"

"I am a real doctor!" he retorted offended. "And it doesn't need a medic, _like me_, to feel it."

Petulantly he offered her his wrist to try. Donna grinned and reached out, taking his pulse with her index and middle finger like she'd seen in crime movies.

And really, she could feel two pulses.

"What if you lose one?" she suddenly wanted to know. "Does it kill you? Do you need both?"

"I need both," the Doctor replied calmly. "But it doesn't directly kill me to lose one. It weakens me, though and it's not a pleasant feeling."

After all this new information, Donna sat back in her seat and the two friends to a long sip from their tea.

"Do you feel better about them now?" the Doctor finally wanted to know. He still saw the shocked look in Donna's eyes when he thought about the dungeons.

"Of course, dumbo! I'm not that easily scared. It just came as a surprise," she replied. She didn't want to admit that it had shaken her image of the very human-like Doctor and she had been scared, no matter what she said. Now that she knew more about it, she could accept it.

All this must have been written on her face because the Doctor suddenly decided he could go a little further. Confidently he pointed out: "I don't get why everyone's so interested in the hearts all the time."

"Do you mean that's not everything you've got two of?" Donna wondered.

The Doctor waggled his eyebrows suggestively at her and Donna felt a flush creeping onto her face. No! He could impossibly mean he had two... Oh, she didn't even want to think about that possibility!... Would that imply Time Ladies also had two...

"Oh, you Space-pervert!" she exclaimed and hit his arm. "I could have lived without _that_ information!" She hit him again and an expression of confusion and agony appeared on his face.

"What's wrong with having two livers?!" he wanted to know and tried to escape another of Donna's blows. The ginger hesitated and gaped at him, unbelieving.

"Livers? If you were talking about those, what was that smug look for?"

"Having two livers is pretty great," he justified and the look reappeared on his face, telling Donna he really had been talking about them.

"W-what did you thought I meant?" he asked, sounding rather sheepish.

"Never mind it," Donna replied shortly.

"But, you-"

"Never. Mind. It. Doctor."

They exchanged an embarrassed look and both had to stifle a grin. Donna took a deep breath then and announced: "I'm just glad that we could sort all that out. No nasty surprises anymore."

"You think that's everything?" the Doctor asked amused. "Time Lords may look like humans but there are countless differences. Organs are just the tip of the iceberg."

Donna gave him an intimidated look.

"What else is there, Martian?"

He put an even smugger look on.

"You'll find out, Miss Noble. Sooner or later."


	2. Part 1b

**Part 1.b: Breathless**

Meeting Jack Harkness was always fun but at the same time straining. Fun because Jack always had one or two funny (and saucy) stories to tell that made Donna giggle and the Doctor blush. Also the Captain knew how to flirt with Donna in a way that wasn't intrusive but flattering – the ginger had a wonderful time with him.

The straining part came later, when Jack left them again. For a reason that was beyond Donna, but probably was concerned with the male ego, the Doctor couldn't hold his tongue for a single second. Donna was used to him being talkative, but after meeting Jack he just went over the top with it.

After he'd finished telling her about why Jack wasn't that brave and funny and what-not (always underlining that they were good friends) he started talking about situations he' been in himself that Jack would never have been able to solve.

Today's story was about the Doctor's fight against a giant squid in a deep lake on an ancient world that was long gone. Donna listened to his monologue, nodding and mumbling agreement at times until she was fed up with it.

"It took me 5 minutes to figure out that it was no octopus but a novempus, which basically means this creature had 9 arms instead of 8 and-"

"Oh, now you're showing off!" Donna interrupted him annoyed. "The 10 minute search, then the fight that took you ages and now 5 minutes you wasted with thinking. _Underwater_! How daft do you think I am? You're not the flippin' Fish Lord, when did you breath?"

"I'm not showing off!" the Doctor replied hurt. "I can hold my breath just longer than humans can!"

Donna snorted dismissively. "The next thing you'll be telling me is that you've got gills!"

"Don't need any! Three words: respiratory bypass system," he announced proudly.

"Oh, now you're just making words up again," Donna rolled her eyes. She had no idea with what kind of naive chicks the Doctor used to travel, but he wouldn't awe her with some techno blah-blah.

"Fine, I'll show you," he decided. Fascinated, Donna watched the Time Lord take a deep breath and then press his lips tightly together. Minutes past and nothing happened except that Donna was sure the TARDIS had never experienced so much silence.

"You're cheating!" Donna said after another couple of minutes past without the Doctor gasping for air. He didn't reply, still holding his breath, but he threw a challenging look at her.

Donna reached out to hold his nose. She was sure he was secretly breathing. Nothing happened but the Doctor demonstratively peeking at his watch. Finally Donna released him and sat back to admire his silent show a little longer.

"How do you do that?" she wanted to know. As an answer, the Doctor raised three fingers and tapped them against his wrist as if they were playing charade. 3 Words.

"This respirational passing nonsense?" Donna asked doubtfully.

"Respiratory bypass system," he spoke again and his voice sounded a little short of breath. "Saved my life umpteenth of times."

"No surprise you can run and run like that without ever stopping," Donna said and the Doctor smiled proudly that he'd once again proved how superior his physiology was to hers (and Jacks). Donna slowly started enjoy all the new information about her Martian, but all those advantages had to mean there were disadvantages, too... or not? The ginger was even more interested to learn about those, she mischievously recognized, someone must wipe that smirk off his face.


	3. Part 1c

**Part 1.c: Getting wasted**

Donna loved nothing as much as travelling in the TARDIS with the Doctor. Seeing all those places, meeting all those people and creatures and feeling more useful and important than she had felt in her entire life. She was sure she would never ever want to go back home. Unfortunately home had its way of closing in on her at times. Today had been one of those days.

Donna had been sitting in the library, waiting for the Doctor to finish his tinkering on the TARDIS and join her, when her upgraded mobile phone rang in her pocket. The ginger had answered the call from her mother and regretted it right away.

Sylvia Noble would just call her because of three things.

1. The world was positively going down.

2. Donna had done something

3. Donna had not done something

Today it had been the third reason – What Sylvia's stubborn daughter had refused to do was marrying and yet again Sylvia decided it was her task to push Donna a little more; she was sure Donna was just remaining single because she wanted to upset her mother. So the blonde woman told Donna about her good friend Nerys' wedding plans and how her baby twins loved their new father.

To cut a long story short, the call of her mother had been enough to remind Donna of one thing she would never find while travelling about – a husband. If she had to decide between a husband and the travelling she would always chose the latter, but this didn't mean she couldn''t lament about the lack of the first.

That was why, when the Doctor finally joined Donna in the library, she had made use of the TARDIS very own alcohol stock. Drinking until a problem was gone, how irresponsible was that? Well, she had needed something to do that she knew her mother wouldn't approve of. Alcohol seemed a good option.

Sniffling, she wiped the last tears out of the corner of her eye and sat up in her seat, a glass with some odd (but quite delicious) alien booze in her hand.

"Having a party?" the Doctor asked ironically, but with a worried undertone and his eyes wandered over the other bottles in front of Donna, two of them already empty. Donna didn't answer. Firstly, because he obviously knew the answer and secondly, because she wasn't sure how slurred her voice would sound.

He walked in slalom around the bottles and sat down next to Donna.

"Do you want to tell me what's wrong?" he asked gently.

Donna shook her head, it started swimming and she abruptly stopped.

"We-ll," he put a thoughtful look on and glanced about. "There's not much that can happen to make you sad in a library... Well, this library anyway. Except you read a really sad book. Did you read a sad book?"

Donna glared at him.

"I'm not crying because of a daft story!" she ranted. Oh, good. Her voice was still useable.

"A daft story?!" the Doctor wondered shocked. "There are many books worth crying for! Some authors simply create wonderful characters and then one day WHAM! They kill them and in such a case crying is a very appropriate way of dealing with such a loss."

Donna decided she was by all means too drunk to put up with this story again.

"Doctor, Dumbledore's dead since 8 years now, get over it," she replied annoyed and before the Doctor could complain about her pert answer she reached out for a bottle with an azure liquid in it and push it into the Doctor's hands. The Time Lord eyed it suspiciously.

"If I get drunk alone in the library it's just sad, but if you join me then..." Donna was sure the sentence had made sentence when she''d begun it. "it's not _that_ sad," she finished slowly.

"You could tell me what upsets you, instead. It's better than drowning it in alcohol," the Doctor reasoned but Donna knew she couldn''t tell him. Not yet. If she would mention the getting married thing he would either try to help her find a husband or he'd put that I-had-a-wife-once-but-now-she's-gone-look on and Donna knew she couldn''t handle either of his reactions.

"I'd rather not," she mumbled and took another sip.

She knew he was still worried and curious but she was all the more grateful when he just nodded, leaving well alone and taking a sip from the blue liquid. He put the bottle down again and grinned.

"I forgot how great this tastes."

The evening went by and Donna's bad mood finally lightened up. The Doctor could do what the alcohol had failed at and cheered her up, even though the booze helped making her giggle about all kinds of silly alien jokes.

The Doctor finished a pun about the Slitheen and Donna burst out into a fit of laughter that made her cry.

"Did you even understand that one?" the Doctor asked her with a slight chuckle.

"Not one word," Donna replied and giggled about the fact that she didn't.

"I guess that means you really had enough of that," the Doctor announced and gently pulled the bottle out of Donna's grip. She watched him collecting all the remnant of their evening and tried not to get distracted by his rather nice backside. Why hadn't she noticed that before? He certainly had a nice bum for such a skinny Martian. Donna snickered about her naughty thoughts but finally came to the conclusion that he may be right, she should head for bed before other parts of his anatomy would get interesting, too.

She sat up, careful not to lose her balance and had to hold onto the sofa firmly so she wouldn't simply fall off it. The Doctor watched her with an amused look.

"How does it come that you're hardly drunk?" Donna asked, even though she reckoned what actually left her mouth was "How you no drunk?"

"Time Lord trick," he winked at her. "Alcohol does affect us, but we can kind of... shrug it off."

"So you planned on staying sober, mean Martian," Donna accused him.

"Someone had to take care of you," the Doctor reminded her. "One day we can switch. Then I'll drink something and you'll look after me," he proposed and Donna nodded. She had no intention to walk all the way to her bed so she simply lay down on the soft couch in the library and snuggled into a big cushion.

"Wait! But you could just get sober again and then I'm useless. That's not fair!" she griped. The Doctor thought about that for a moment while putting a blanket over his companion.

"There's always the ginger beer...," he mumbled more to himself.

"Huh?" Donna raised her head attentively.

"Oh, nothing! Nasty stuff this ginger beer is, it has a way to get straight into our bloodstream and... well, the consequence is a very drunk Time Lord, nothing we should try."

Ugh, this sentence had been too long. Donna frowned and finally lay back against the pillow. She had no idea how this ginger beer worked, but one thing was sure. She had to get some of it onboard of the TARDIS... At least if she could remember it tomorrow.


	4. Part 1d

**Part 1.d: A matter of ancestry **

_A/N: I wasn't sure if I should publish this at all. It's kinda weird and pretty pointless, but then again I put some effort into the scenery, so I guess it's worth a try. As always: let me know what you think & how I can improve~_

* * *

The Harlequin-guard tilted its head at Donna, she saw him through the bars of the cell, and the shiny bells on its hat silently jiggled. At first those monochrome clowns had scared Donna silly, but now, two solid weeks in their clutches, the only thing she felt while looking at them was anger.

She remembered the day she and the Doctor had come here. It had been the morning after she'd emptied half of the TARDIS's alcohol stock and suffered from the nastiest hang-over of her life. The Doctor had offered to take her to the most silent planet in creation and, feeling too sick to argue, Donna had agreed.

The planet turned out to be looking like an old movie, not only because of the lack of any colour, but also because the whole landscape showed criss-crossed glitches now and then, just like a broken telly. The only creatures living there were the natives, those colourless harlequins that never spoke a word. And since they never said anything, couldn't write or draw, they had no names.

Donna hadn't liked the planet much. The residents were creepy clowns who never talked and the surroundings looked like a broken TV-show, but at least it had been silent.

And then the Doctor had come.

The most talkative creature of all time on planet mute – Donna should have known this wouldn't end well and of course: Hardly twenty minutes after their appearance they had been thrown into prison. No one told them why, natch, but the ginger was sure the Doctor's voice had simply been too much for this planet.

This was partly why she was cross with her Martian. She was also annoyed because he hadn't found a way to escape, yet. Sharing a poky cell with him didn't exactly pour oil on the troubled water of their friendship, so they hadn't been talking to each other for two days. This meant there had been no _single_ sound in two days. The floor was designed to swallow every sound of footsteps and the shackles were muted, too.

Donna was sure that she was slowly losing her mind in all this silence and for the first time in ages she wished the Doctor would throw one of his endless monologues – of course she was too stubborn to ask him and he was too stubborn to simply start. They were in a stalemate.

The harlequin tilted its head at her again, just as if it was mocking her, and Donna poked her tongue out at it. The clown made a startled face. Donna grinned then she recognized a grin on the Doctor's face, too, from the corner of her eye. He saw her, seeing him and stopped smiling, instead he put his icy, pouting look back on and so did Donna.

She looked back at the harlequin and winced. The monochrome alien was poking its tongue out at her and now looked really creepy. When it recognized Donna's shock, it grinned like she'd done before and then stopped abruptly to look icily back at her, just like the Doctor. It was mimicking them.

Donna shuddered and pulled her legs up onto the seat of the bed. She hated those aliens. She wanted to go back to the TARDIS and she wanted a cup of tea and a real meal – not those colourless mashes.

And, first of all, she wanted her bathroom! Of course they offered them a loo and fresh water to shower and brush their teeth, but well… this was hardly enough. Donna's hair was a mess and to her misfortune she'd chosen to wear a dress that showed quite a lot of her legs. She hated how women in movies could spent years in dungeons or other hostile surroundings and always had perfectly shaved legs.

Her mood darkened even more when she threw a glare at the Doctor. Great, he looked brilliant, as if they had just left the blue box. Oh, she hated him for this the most right now. She wrapped her arms around her legs to hide them and rested her chin on her knees, death-glaring at the handsome Martian.

Until he caught her look. It must have looked really peeved because he instantly put his beaten-puppy look on. Now Donna felt guilty. She softened her look and sighed, finally she had had enough of this fight.

"Oh, stop looking at me like that," she told the Doctor who instantly smiled brightly at her.

"You're not mad at me anymore?" he asked and the words bubbled out of him. The punishment of silence really must have hurt him.

As an answer, Donna mumbled something undistinguishable into her wrists. He positively beamed at her.

"Great, because I'm working on a plan to get us out, don't worry! We'll be back with the old girl in a tick," he promised. "Of course I'm a little stuck with the plan, because, oh, I missed talking to you! I can never think when I have no-one to talk, you know? So, as I said, I'm just a little stuck, but now that we're talking with each other again I'm sure I can think of something!"

Donna rolled her eyes, amused. How had he managed to keep silent for that long? It nearly must have killed him, the stubborn git. While Donna kept thinking that to herself the Doctor hadn't stopped talking for a second.

"-which could be our way out if we don't mess it up and- what's wrong with your legs by the way? Are you hurt, Donna?" he suddenly changed the subject and eyed his companion up. Donna blushed and pulled her legs even closer to herself.

"No, I'm fine. Just get us out of here," she replied firmly.

"Are you sure? I've been watching you for the past days- Err, not on purpose , of course, just looking and recognizing- not that you're not worth watching, it's just- It'd be creepy and- Never mind, I just thought: She seems to be uncomfortable about her legs, that what I thought," now he was talking so fast the he was interrupting himself in doing so.

"Doctor, slow down or you'll bite your tongue off," Donna mocked. "And I am not hurt I just-," her cheeks burned embarrassed. "I'm just missing my own bathroom, alright?"

The Doctor frowned, obviously completely puzzled.

"They have a toilet, just down the corridor," he told her slowly, wondering how she'd managed to survive the past two weeks without that knowledge.

"Not that, dumbo!" she jabbed him in the ribs. "There are things a woman needs to do now and then and obviously those clowns've never heard of such problems." Donna shot him a don't-be-so-thick-glare.

The Doctor blinked blankly at her.

"So… it's that time of the month for you?" he carefully asked. In return Donna's face grew even redder.

"Not that!" she snapped angrily and the movement in front of their cell told Donna that the harlequin had never ever heard someone shout before and just jumped in shock. Grimly satisfied that she'd repaid the creep he'd given her, she leaned back against the cell wall and said, as nonchalant as possible: "I need a shave, ok. I know you blokes just expect women to exist with a smooth skin and all that, but the reality is different. Sorry to disappoint your expectations."

To her surprise the Doctor didn't look disgusted or embarrassed. He just chuckled softly.

"Are you laughing at me?!" Donna wondered hurt.

"No, why should I?" he smiled. "The smooth skin is just a temporary ideal of beauty in your culture. In fact humans still have the predisposition to grow a fur. Look at it as a memento from your ancestors. That's nothing to be ashamed of."

"Oi!" she exclaimed. "Are you calling me an ape?!"

"We-ll," he shrugged. Donna started hitting his arm and he had to take some steps back to escape her attack.

"You're such an idiot!" she growled. "Don't pretend the almighty Time Lords have always been like that! I bet your ancestors weren't much more glorious than mine!"

"I did not evolve from apes!" he replied. "In fact, Time Lords are closer related to Terileptil than to humans."

Donna remembered a reptile-like alien the Doctor had shown her some time ago, that he'd called "Terileptil".

"So that's why you look like you've smuggled a shaver in here?" she wondered annoyed. "Because your people evolved from frogs instead of apes? And that's something you feel superior for?"

The Doctor threw a hurt glare at her.

"We didn't evolve from them, we are just related."

"_Closely_ related."

"At least I don't have to worry about growing a fur after a few days!"

"Right, you couldn't grow a beard if you tried, Time_boy_!"

A gloved hand grabbed Donna's arm all of a sudden. She startled and turned around to see that two of the muted clowns had entered their cell. Before she or the Doctor could wonder what was going on, they were dragged out of the poky prison.

Finally they were out of there! Donna blinked up at the sun in the sky and a happy laugh broke form her lips.

"They let us out, but why?!"

The Doctor slowly rubbed his neck like he wasn't entirely happy about what just happened. Being thrown out of a prison seemed to be something new, even for him.

"Our row… I guess we've been a little _too_ loud for them so they simply chucked us out…"

Donna beamed. Maybe this meant they hadn't exactly made some new friends, but she could do without creepy clowns on her Christmas card list anyhow.

"That's fine with me," she said. "I just want to go back. I am knackered and I miss my bathtub."

The Doctor shook his head with a smile.

"Humans. You're so fragile. Sometimes I wonder how you manage not to get extinct."

"Oh, because you Time Lords are so much better than we are?" Donna asked, slowly she'd had enough of this nonsense.

"Not better, just… more carefully arranged."

Donna snorted and opened her mouth to shoot him a reply, but the Doctor interrupted her: "Let's not fight about this again. I thought you just wanted to go back to the TARDIS?"

"Fine," Donna agreed reluctantly and linked arms with the Doctor. "But this isn't over," she promised.

"I knew it wouldn't be that easy," he mumbled.


End file.
